The judge had wanted a trial this year, but it will take significantly longer to prepare because the prosecution is seeking a death sentence if Ciancia is convicted.

Prosecutors said in court papers that they would seek execution because Ciancia intentionally targeted federal employees, and terrorized passengers and airport workers.

Ciancia, 24, a New Jersey native, has pleaded not guilty to murder and other charges in the killing of Transportation Security Administration Officer Gerardo Hernandez, 39, and the wounding of three other people at LAX on Nov. 1, 2013.

U.S. District Judge Philip Gutierrez said he thought the case could be tried by September, but he's willing to push it back to early next year. However, he said "something tremendous" would have to occur to delay it further.

Public defenders have said they have a mountain of evidence to digest. Prosecutors have disclosed at least 10,000 pieces of evidence, or 150 DVDs full of material.

Death penalty cases are more complex because lawyers have to prepare for guilt and penalty phases, and that often involves intensive digging for information from people who knew the defendant, even dating back to childhood.

"There's often a serious psychiatric component to these cases," said attorney Marilyn Bednarski, a former federal defender who represented Buford Furrow, a white supremacist who killed a Filipino postal worker and wounded five people in a 1999 shooting at a Los Angeles Jewish community center. "It's just not normal behavior. Often people are terribly mentally ill and those things take a long time to investigate."

Federal death penalty cases are relatively rare.

U.S. prosecutors have sought the punishment about 500 times since the federal death penalty was reinstated in 1988, said Richard Dieter, executive director of the Death Penalty Information Center. During that time, there were 79 death sentences, but only three people have been executed.